Business Notes GEMS

As a girl's best friend, diamonds are becoming more dear. De Beers Consolidated Mines, which controls 80% of the diamond market, said last week it will raise prices for rough gemstones by 13.5%. All told, the company's average prices have risen 52% since 1982, bringing the price of a one-carat flawless diamond to more than $17,000.

The diamond cartel has been able to impose the price increases largely because of intense demand from Japan, where the strong yen has made imported gems a bargain and young couples have developed a newfound fondness for diamond engagement rings. While many diamonds have become more expensive in the U.S., sales still sparkle aplenty. One reason: single professional women are increasingly buying their own gems -- in discreet sizes.